It's close to Vietnam, place in eastern region (8)
I believe the answer is:
malaysia
'region' is the definition.
(Malaysia is an example)
'it's close to vietnam place in eastern' is the wordplay.
'it's close to' suggests the final letters (the 'close' to the word).
'place' becomes 'lay' (laying is a kind of placing).
'in' is an insertion indicator.
'eastern' becomes 'asia' (I am not sure about this - if you are sure you should believe this answer much more).
The final letter of 'vietnam' is 'm'.
'lay' going inside 'asia' is 'alaysia'.
'm'+'alaysia'='MALAYSIA'
Can you help me to learn more?
(Other definitions for malaysia that I've seen before include "Eastern state" , "SE Asian state" , "Country of SE Asia" , "Kuala Lumpur is its capital" , "land abroad" .)